Remote sensing systems are frequently employed that ‘sense’ the environment at a distance by means of electronic sensors. Such electronic sensors will typically attempt to intercept fields that are radiated or reflected by objects of interest.
The intent of deploying such sensors is to aid in answering two fundamental questions:                Where is the object of interest ?        What is the object of interest ?        
To aid in answering the first question, Huygen's principle is often utilised. This principle essentially dictates that signals propagating from a source through space have (at some distance from the source) wavefronts that are perpendicular to the direction of propagation. To assess the direction of arrival of a signal, a sensor must deduce the orientation of the wavefront carrying the signal, and the DOA will be perpendicular to that. To accomplish this, sensors will use an aperture of non-zero dimension.
To aid in answering the second question, a sensor may attempt to analyse the signal that is received from the object of interest.
In conjunction with the development of sensor systems, much effort has been devoted to the development of electronic counter-measures that platforms might deploy that attempt to deceive opposing force's sensors.
Jamming is one approach to countermeasures, that aims to emit a signal that is so strong, all other signals received by the opposing forces's sensors are ‘blotted out’. However, if the sensors incorporate appropriate filters, the effect of the jamming signal can be nullified, and the ability of the sensor to monitor other targets may be unhindered.
Furthermore, the sensor will be able to determine the source direction of the jammer. Another approach to countermeasures is to transmit deceptive signals, with the intent of deceiving the opposing sensor into deducing that the platform is something other than that which it really is. An example may be a submarine transmitting underwater acoustic signals reminiscent of whale mating calls.
The drawback of this approach is that transmission of such a signal will enable opposing force sensors to localise the source of the emanation. Hence this approach trades off helping opposing forces find the platform, against hindering opposing forces understand the identity of the platform. This trade might actually give away more than it gains for own forces.
Both jamming and the transmission of deceptive signals suffer from the same common problem. Transmission of a signal through space creates wavefronts that essentially create an arrow pointing back to the source of the signal, and help opposing forces answer the first fundamental question.
It is an object of the present invention to provide an electronic countermeasure capable of transmitting signals that deceive the opposing force as to the where the source is.